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Role of helicity of a-helical antimicrobia peptides to improve specificity

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Protein & Cell 2014年第8期5卷 631-642页

作者： Yibing Huang liyan He Guirong Li Naicui Zhai Hongyu Jiang Yuxin Chen Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education Jilin University Changchun 130012 China National Engineering Laboratory for AIDS Vaccine Jilin University Changchun 130012 China School of life Sciences Jilin University Changchun 130012 China The First Hospital Jilin University Changchun 130021 China

A major barrier to the use of antimicrobial peptides as antibiotics is the toxicity or ability to lyse eukaryotic cells. In this study, a 26-residue amphipathic a-helical antimicrobial peptide A12L/A20L （Ac-KWKSFLKTFKSLK KTVLHTLLKAISS-amide） was used as the framework to design a series of D- and L-diastereomeric peptides and study the relationships of helicity and biological activi- ties of o-helical antimicrobial peptides. Peptide helicity was measured by circular dichroism spectroscopy and demonstrated to correlate with the hydrophobicity of peptides and the numbers of D-amino acid substitu- tions. Therapeutic index was used to evaluate the selectivity of peptides against prokaryotic cells. By introducing D-amino acids to replace the original L-amino acids on the non-polar face or the polar face of the helix, the hemolytic activity of peptide analogs have been significantly reduced. Compared to the parent peptide, the therapeutic indices were improved of 44-fold and 22-fold against Gram-negative and Gram- positive bacteria, respectively. In addition, D- and L-diastereomeric peptides exhibited lower interaction with zwitterionic eukaryotic membrane and showed the significant membrane damaging effect to bacterial cells. Helicity was proved to play a crucial role on peptide specificity and biological activities. By simply replacing the hydrophobic or the hydrophilic amino acid residues on the non-polar or the polar face of these amphipathic derivatives of the parent peptide with D-amino acids, we demonstrated that this method could have excellent potential for the rational design of antimicrobial pep- tides with enhanced specificity.

关键词： antimicrobial peptides （AMPs） peptideantibiotics helicity secondary structure diastereomericpeptides specificity therapeutic index

Study on Precursory Features of the Lop M_S6. 0 Earthquake Based on GPS Continuous Observation Data and Mobile Gravity Data

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Earthquake Research in China 2015年第3期29卷 386-393页

作者： Zhu Zhiguo li guirong School of Earth Sciences and Resources Chang'an University Earthquake Administration of Xinjiang Uygur Autonomous Region

Through calculating and analyzing of GPS continuous observation data and mobile gravity data,the study results from the data are as follows.( 1) The different movement rate of the fault ends provides conditions for stress accumulation.( 2) The high value zone of gravity anomaly appeared in the monitoring area before the earthquake,and gravity variation contour lines are parallel to the strike of fault; and the process of enhancingweakening-enhancing appeared in the regional gravity field before earthquake.

关键词：地震发生重力数据观测数据前兆特征 GPS 区域重力场应力积累运动速率

Detecting Primary Precursors of January Surface Air Temperature Anomalies in China

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Journal of Meteorological Research 2017年第6期31卷 1096-1108页

作者： guirong TAN Hong-li REN Haishan CHEN Qinglong YOU Key Laboratory of Meteorological Disaster of Ministry of Education/Joint International Research Laboratory of Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science &Technology Laboratory for Climate Studies/CMA–NJU Joint Laboratory for Climate Prediction Studies National Climate CenterChina Meteorological Administration Department of Atmospheric Science School of Environmental Studies China University of Geoscience

This study aims to detect the primary precursors and impact mechanisms for January surface temperature anomaly （JSTA） events in China against the background of global warming, by comparing the causes of two extreme JSTA events occurring in 2008 and 2011 with the common mechanisms inferred from all typical episodes during 1979- 2008. The results show that these two extreme events exhibit atmospheric circulation patterns in the mid-high latitudes of Eurasia, with a positive anomaly center over the Ural Mountains and a negative one to the south of Lake Baikal （UMLB）, which is a pattern quite similar to that for all the typical events. However, the Eurasian teleconnection patterns in the 2011 event, which are accompanied by a negative phase of the North Atlantic Oscillation, are different to those of the typical events and the 2008 event. We further find that a common anomalous signal appearing in early summer over the tropical Indian Ocean may be responsible for the following late-winter Eurasian teleeonnec- lions and the associated JSTA events in China. We show that sea surface temperature anomalies （SSTAs） in the preceding summer over the western Indian Ocean （WIO） are intimately related to the UMLB-like circulation pattern in the following January. Positive WIOSSTAs in early summer tend to induce strong UMLB-like circulation anomalies in January, which may result in anomalously or extremely cold events in China, which can also be successfully reproduced in model experiments. Our results suggest that the WIOSSTAs may be a useful precursor for predicting JSTA events in China.

关键词： Eurasian teleconnection anomalous temperature in China seasonal climate prediction SST anomaly western Indian Ocean model experiment

Active Control Law Design for Flutter/LCO Suppression Based on Reduced Order Model Method

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Chinese Journal of Aeronautics 2010年第6期23卷 639-646页

作者： Chen Gang li Yueming Yan guirong MOE Key Laboratory for Strength&Vibration School of AerospaceXi’an Jiaotong UniversityXi’an710049China

Active stability augmentation system is an attractive and promising technology to suppress flutter and limit cycle oscillation (LCO). In order to design a good active control law, the control plant model with low order and high accuracy must be provided, which is one of the most important key points. The traditional model is based on low fidelity aerodynamics model such as panel method, which is unsuitable for transonic flight regime. The physics-based high fidelity tools, reduced order model (ROM) and CFD/CSD coupled aeroservoelastic solver are used to design the active control law. The Volterra/ROM is applied to constructing the low order state space model for the nonlinear unsteady aerodynamics and static output feedback method is used to active control law design. The detail of the new method is demonstrated by the Goland+ wing/store system. The simulation results show that the effectiveness of the designed active augmentation system, which can suppress the flutter and LCO successfully.

关键词： limit cycle oscillation aeroelasticity reduced order model active control law static output feedback

The Impacts of Highly Resourced Vocational Schools on Student Outcomes in China

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China & World Economy 2020年第6期28卷 125-150页

作者： Guirong Li Jiajia Xu liying li Zhaolei Shi Hongmei Yi James Chu Elena Kardanova Yanyan li Prashant Loyalka Scott Rozelle International Center for Action Research on Education School of EducationHenan UniversityChina Henan University of Engineering China Freeman Spogli Institute Stanford UniversityUSA School of Advanced Agricultural Sciences Peking UniversityChina Higher School of Economics National Research UniversityRussia School of Education Henan UniversityChin Graduate School of Education Stanford UniversityUSA

Policymakers in developing countries have prioritized the mass expansion of vocational education and training(VET).This study examines whether the quality of VET in developing countries increases by investing greater resources per student.To achieve this goal,we examine the impacts of attending model schools(which have far more resources per student)on a range of student cognitive,non-cognitive,and behavioral outcomes.Using representative data from a survey of approximately 12,000 VET students from China,multivariate regression and propensity score matching analyses show that attending model vocational high schools do not benefit student outcomes,despite their substantially greater resources.

关键词： non-cognitive skills school expenditure student achievement vocational education and training

教育匹配影响居民主观幸福感的路径研究——基于中国家庭追踪调查数据的实证分析

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河南大学学报（社会科学版） 2023年第4期63卷 117-125,155页

作者：李桂荣李文华河南大学教育学部河南开封475004 河南大学教育行动国际研究中心河南开封475004

教育与工作的匹配状况不仅是评估教育投资效益的重要指标,而且能够反映教育投入与产出的平衡状态。在当前我国致力于提高人们幸福生活的新形势下,教育匹配是否能够有效提高劳动者的主观幸福感,需要进行实证研究。基于2018年和2020年中... 详细信息

教育与工作的匹配状况不仅是评估教育投资效益的重要指标,而且能够反映教育投入与产出的平衡状态。在当前我国致力于提高人们幸福生活的新形势下,教育匹配是否能够有效提高劳动者的主观幸福感,需要进行实证研究。基于2018年和2020年中国家庭追踪调查(CFPS)数据,运用有序Probit模型和多重中介效应检验方法,分析教育匹配、收入水平与居民主观幸福感的关系,研究表明,随着教育匹配趋向合理,居民主观幸福感得到提高;收入水平和居民主观幸福感之间存在“伊斯特林悖论”,且满足福利经济学的相对收入假说,即绝对收入不能提高居民主观幸福感,相对收入显著提高了居民主观幸福感;收入水平作为教育匹配影响居民主观幸福感的一个重要渠道,主要是通过相对收入实现,绝对收入的中介效应不显著。基于此,提高居民主观幸福感,应从提高教育质量、优化教育结构、推动教育系统与劳动力市场均衡发展等方面进行政策建设。

关键词：教育匹配主观幸福感收入水平绝对收入相对收入

A Clicked Tetrathiafulvalene-oxyquinoline Dyad as an Optical and Electrochemical Zn2＋ Probe

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Chinese Journal of Chemistry 2012年第2期30卷 254-258页

作者： Zhao,Bangtun liu,lianwei li,Xiaochuan Qu,guirong Department of Chemistry Luoyang Normal UniversityLuoyangHenan 471022China College of Chemistry and Environmental Science Henan Normal UniversityXinxiangHenan 453007China

一篇小说点按 tetrathiafulvalene 衍生物 3 生二个 8-oxyquinoline 组通过光、电气化学的变化为 Zn2+ 的选择察觉被综合。Zn2+ 和 Cd2+ 的增加在荧光紧张导致了一个重要变化，它对从 oxyquinoline 和 1,2,3-triazole 戒指的提高 chelat... 详细信息

一篇小说点按 tetrathiafulvalene 衍生物 3 生二个 8-oxyquinoline 组通过光、电气化学的变化为 Zn2+ 的选择察觉被综合。Zn2+ 和 Cd2+ 的增加在荧光紧张导致了一个重要变化，它对从 oxyquinoline 和 1,2,3-triazole 戒指的提高 chelation 的荧光效果可归因。3 的电气化学的潜力测试的另外的金属阳离子相对那些向更积极的价值面对 Zn2+ 被转移。

关键词：四硫富瓦烯羟基喹啉电化学势光学双链探头锌选择性检测

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教育匹配的就业质量效应研究

首都经济贸易大学学报 2022年第4期24卷 69-80页

作者：李文华李桂荣河南大学教育学部河南开封475004 河南大学教育行动国际研究中心河南开封475004

在教育匹配视角下,从工作收入、职业发展、工作稳定性和工作满意度四个方面构建劳动者就业质量指标体系;基于2018年中国家庭追踪调查(CFPS)数据,使用倾向得分匹配(PSM)方法实证检验教育匹配的就业质量效应,并分样本估计不同类型劳动者... 详细信息

在教育匹配视角下,从工作收入、职业发展、工作稳定性和工作满意度四个方面构建劳动者就业质量指标体系;基于2018年中国家庭追踪调查(CFPS)数据,使用倾向得分匹配(PSM)方法实证检验教育匹配的就业质量效应,并分样本估计不同类型劳动者的组群差异。结果表明,教育匹配显著提升劳动者的就业质量,且使用PSM方法进行检验后,这一结论依然成立;教育匹配对劳动者的工作收入、职业发展、工作稳定性和工作满意度都有很强的影响力。异质性分析结果显示,高学历、男性劳动者教育匹配对就业质量的影响显著高于低学历、女性劳动者,且教育匹配对就业质量的提升效应主要来自年轻劳动者;教育匹配对不同地区和城乡劳动者就业质量的促进作用并没有显著差异。研究结论对于提高教育质量、完善人才培养模式、实现人尽其才的劳动力就业市场环境具有重要的政策启示意义。

关键词：教育匹配过度教育就业质量劳动力就业人才培养

读中职真的“不值”吗——基于就业质量视角的实证分析

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教育发展研究 2022年第13期42卷 39-44,56页

作者：李桂荣李文华河南大学教育学部开封475004 河南大学教育行动国际研究中心开封475004

就读于中等职业学校能否带来满意的教育回报一直是学生和家长进行教育选择时关注的焦点问题,也是国家教育改革创新的重要参考依据。文章采用CGSS2013、2015和2017年微观调查数据,从就业质量的视角实证分析中等职业教育在不同情况下的就... 详细信息

就读于中等职业学校能否带来满意的教育回报一直是学生和家长进行教育选择时关注的焦点问题,也是国家教育改革创新的重要参考依据。文章采用CGSS2013、2015和2017年微观调查数据,从就业质量的视角实证分析中等职业教育在不同情况下的就业市场回报及其内部机制。结果表明,中职教育劳动者相比初中学历劳动者具有较高的就业质量回报;在同等教育水平下,中职教育劳动者相比普通高中劳动者也具有一定的就业质量优势;中职教育劳动者通过学习投入、认知能力和信息获取等中介渠道,进一步提升了相对于初中学历劳动者的就业质量;在不同时期,中职教育劳动者相对初中学历劳动者的就业质量均具有明显优势,且中职教育劳动者的就业质量随着毕业年份呈现先增加后减小的“倒U”型特征。基于此,为回应中职教育的发展价值问题,本文从贯彻落实《职业教育法》的角度提出相关政策建议。

关键词：中等职业教育就业质量教育回报职业教育法 CGSS数据